Many commonly used dielectric ceramic materials are based on the titanate system. The desired properties for dielectric ceramics for use as dielectric resonators, substrates or multilayer ceramic capacitors are a high dielectric constant, a high Q and stable temperature characteristics. Low firing temperatures are advantageous since they permit the use of cheaper lower melting point electrode materials.
One prior art approach employed Ba.sub.2 Ti.sub.9 O.sub.20 to develop a dielectric ceramics having high Q values. While barium nonatitanate is a suitable material, the temperature coefficient of frequency is generally fixed and cannot be varied without changes in stoichiometry that can produce a second phase which is deleterious to Q in the microwave region. Additionally, the best Q obtained for conventional Ba.sub.2 Ti.sub.9 O.sub.20 is only about 9000.